Method for the wavelength calibration of a spectrometer

摘要

The invention concerns methods for the wavelength calibration of spectrometers and in particular secondary spectrometers which achieve considerably better calibration accuracies than the conventional peak search methods especially for spectrometers with a relatively large bandwidth. The methods according to the invention are based on the principle of a stepwise relative shift of corresponding measured-value blocks of a model and calibration spectrum where a correlation value is calculated for each shift step. A shift value is determined for each measured-value block at which the correlation value reaches an optimum. A value pair consisting of a position marker of the measured-value block and the associated shift value is determined for each measured-value block. These value pairs represent the design points for fitting to a suitable assignment function. The coefficients obtained in this manner can be used directly as coefficients of a wavelength assignment or be combined with the coefficients of an existing first wavelength assignment in that they for example replace these coefficients or are offset against the coefficients of an existing first wavelength assignment.